scholarly journals Preparation and Characterization of PEG-PLA Genistein Micelles Using a Modified Emulsion-Evaporation Method

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Qiuchen Cheng ◽  
Wen Qin ◽  
Yanhong Yu ◽  
Guojian Li ◽  
Jizhou Wu ◽  
...  

The objective of this study is to improve the bioavailability of genistein by encapsulation with polyethylene glycol-polylactic acid (PEG-PLA) copolymers. Genistein micelles (GMs) prepared using a modified emulsion-evaporation method were more stable than those made with the original method. The effect of polyvinyl alcohol, Tween 80, sonication time, PEG-PLA/genistein ratio, and organic phase (acetone)/H2O ratio on the size, polydispersity index, encapsulation efficiency, and drug loading efficiency of GMs was investigated. GMs were obtained and characterized under optimal experimental conditions. For long-term storage, GMs were lyophilized by freeze drying with trehalose to produce genistein lyophilized powder (GLP). The analysis of GLP by Fourier-transform infrared spectroscopy and differential scanning calorimetry showed that genistein was successfully incorporated into the micellar structure. In vitro release experiments revealed that the incorporation of genistein into PEG-PLA copolymers significantly improved its solubility and bioavailability. GLP was more potent in inhibiting the proliferation of HSC-T6 cells than genistein. Treatment with GLP at 10–20 μg/mL for 48 h significantly inhibited the protein expression of α-smooth muscle actin and collagen I in HSC-T6 cells compared with the control. These data demonstrated that the improved solubility and bioavailability of genistein in the form of GLP enhanced its antifibrotic effect in vitro.

2015 ◽  
Vol 11 (4) ◽  
pp. 3453-3462
Author(s):  
Paolo Yammine ◽  
Therese Maarawi ◽  
Dima Moussa ◽  
Roula Abdel-Massih ◽  
Rima Kassab ◽  
...  

Microencapsulation by the solvent evaporation technique was used to formulate Indomethacin-loaded poly(DL-lactide-co-caprolactone) microspheres with three different surfactants: Tween 80, Span 80, and Polyvinyl alcohol. Different formulations were prepared by changing drug masses, while keeping the quantities of the polymer and of the surfactant constant. The prepared microspheres were evaluated for drug content, particle size, morphology, drug-polymer interaction, stability, in vitro release, and cytotoxicity assays. Comparison was done to study the effects of the surfactant type on their characteristics. Microspheres presented a spherical and porous profile and were characterized by the stable character of the encapsulated drug. The usage of the Polyvinyl alcohol revealed the highest percent drug entrapment and drug loading, the biggest particles sizes, and the lowest drug release rate. It was the opposite in the case of Tween 80. A negligible cytotoxic effect was noted on Polyvinyl alcohol formulations having the highest drug content. Polymeric microspheres were used efficiently as a delivery system for Indomethacin. Changing the surfactant type had many advantages on drug encapsulation and release rate.


2010 ◽  
Vol 30 (5) ◽  
pp. 365-373 ◽  
Author(s):  
Asli Deniz ◽  
Asli Sade ◽  
Feride Severcan ◽  
Dilek Keskin ◽  
Aysen Tezcaner ◽  
...  

CLX (celecoxib) is a highly hydrophobic non-steroidal anti-inflammatory drug with high plasma protein binding. We describe here the encapsulation of CLX in MLVs (multilamellar vesicles) composed of DSPC (1,2-distearoyl-sn-glycero-3-phosphocholine) and variable amounts of cholesterol. The effects of cholesterol content on liposome size, percentage drug loading and in vitro drug release profiles were investigated. Differential scanning calorimetry and FTIR (Fourier-transform infrared) spectroscopy were used to determine molecular interactions between CLX, cholesterol and DSPC. The phase transition temperature (Tm) of vesicles was reduced in a synergistic manner in the presence of both CLX and cholesterol. Encapsulation efficiency, loading and release of CLX decreased with increasing cholesterol content. FTIR results indicated that this decrease was due to a competition between CLX and cholesterol for the co-operativity region of the phospholipids. In the presence of cholesterol, CLX was pushed further into the hydrophobic core of the bilayer. However, MLVs prepared with DSPC only (without cholesterol) exhibited the lowest ability for drug retention after 72 h. Our results indicated that CLX, without the requirement of modifications to enhance solubilization, can be encapsulated and released from liposomal formulations. This method of drug delivery may be used to circumvent the low bioavailability and systemic side effects of oral CLX formulations.


Author(s):  
J P Raval ◽  
D R Naik

Designing and evaluating a multiparticulate controlled release dosage form, to increase the efficacy of acyclovir (a selective antiherpes agent). Spray drying technique for microsphere production is compared with novel solvent evaporation-matrix erosion technique for variable drug loading in different concentration of ethyl cellulose. The microspheres were characterized for physicochemical properties. The microspheres sizes were ranged from 7-25 μm. The spray dried microspheres had better encapsulation efficiency (up to 91%) compared to that of novel solvent evaporation-matrix erosion technique microspheres. Scanning electron microscopy confirmed spherical geometry due to high cross-linking density. Differential scanning calorimetry, Fourier-transform infrared spectroscopy and x-ray diffraction studies showed chemical stability and intactness of entrapped drug in the microspheres. In vitro release of acyclovir from spray dried microspheres continued for longer period compared to novel solvent evaporation-matrix erosion method. Overall, the release studies depended on the concentration of ethyl cellulose, extent of drug loading, and the technique used to prepare microspheres. Thus, marked retardation of drug release may provide a useful effective anti-retroviral drug therapy.  


Author(s):  
Monika D. Kumbhar ◽  
Manisha S. Karpe ◽  
Vilasrao J. Kadam

Background: Eperisone hydrochloride possesses short biological half-life due to first pass metabolism resulting in low bioavailability and short duration of response with toxic effects, ultimately limits its utilization for treatment of muscle spasm. Objective: In view of this background, current study was designed for the development of Eperisone hydrochloride-loaded microemulsion and Eperisone hydrochloride-loaded microemulsion based cream for topical delivery and compared it with conventional cream. Methods: Firstly, water-in-oil microemulsion was prepared by spontaneous emulsification method. The concentration of components was found out from existence of microemulsion region by constructing pseudoternary phase diagram. The oil was selected on the basis of drug solubility effect on the drug release, whereas surfactant and cosurfactant were screened on the basis of their efficiency to form microemulsion region. The influence of components on microemulsion formation, drug release capacity, permeation was studied by differential scanning calorimetry, X-ray diffraction, in-vitro release and ex-vivo drug permeation studies respectively. By using microemulsion, the cream was prepared for proving optimum structure for topical application. Microemulsion was evaluated for droplet size, zeta potential, pH, viscosity and conductivity. Besides the cream was characterized for pH, rheology and stability. Permeation of EPE from microemulsion across the rat skin was evaluated and compared with conventional cream. Results: The microemulsion consisting Isopropyl Myristrate/Water/Span 80:Tween 80 (50/8/42% by weight) possessed droplet size of 95.77nm, zeta potential of −5.23 mV with 7.25 pH and conductivity near to zero (<0.05mScm-1). Physical parameters of the cream were satisfactory, also 2.33-fold higher permeation and 1.57-fold higher release observed as compared to conventional cream. Conclusion: It can be concluded that Eperisone hydrochloride-loaded microemulsion and its cream is being effectively used for muscle spasticity by topical route.


Author(s):  
Panoraia I. Siafaka ◽  
Emre Şefik Cağlar ◽  
Katerina Papadopoulou ◽  
Vasilios Tsanaktsis ◽  
Ioannis D. Karantas ◽  
...  

Background: Glibenclamide is a lipophilic drug widely used in type 2 diabetes treatment. However, its low bioavailability limits its use. Thus, novel formulations should be applied to improve the drug’s bioavailability. Objectives: This study aimed to develop alternative carriers for oral delivery of glibenclamide. For this purpose, two biocompatible polymers, poly(e-caprolactone) and poly(butylene adipate) were formulated as microparticles (MPs) capable of loading the antidiabetic drug. Methods: In this regard, as microparticle fabrication approach, the modified emulsion solvent evaporation method was applied. Physicochemical evaluation of the prepared microparticles included the examination of their morphology, degradation rate, and thermal properties. Drug entrapment, drug loading, and particle size were also investigated. Simulated intestinal medium and body fluid at 37oC were selected as dissolution media. Differential scanning calorimetry was used to investigate the crystal properties of the microparticles and drugs. Results: The developed microparticles had sizes between 0.5 and 4 μm. Poly(butylene adipate) based microparticles had a smooth surface, whereas poly(ε-caprolactone) based microparticles showed a porous surface. The DSC thermogram revealed the amorphization of the drug. Hydrolysis results exhibited a very low mass loss, while in vitro release results depicted that the dissolution rate of the prepared microparticles was higher than that of pure glibenclamide demonstrating a prolonged pattern which is ideal for minimizing the daily dose of glibenclamide. Conclusion: In this study, novel carriers for glibenclamide were successfully prepared with promising future use.


2018 ◽  
Vol 83 (11) ◽  
pp. 1243-1259
Author(s):  
Oum Larbi ◽  
Haouaria Merine ◽  
Youssef Ramli ◽  
Fawzia Toumi ◽  
Kaddour Guemra ◽  
...  

Hydrochlorothiazide (HCTZ), which was developed and introduced in the late 1950s, is still one of the most frequently employed drugs in antihypertensive treatments. Its poor aqueous solubility is one of the reasons for its limited bioavailability after oral administration. The present paper provides details of the preparation of HCTZ-loaded microspheres by the solvent evaporation technique. A total of seven formulations were prepared using ethyl cellulose, poly(?-caprolactone) (PCL), ?-cyclodextrin (?-CD) and synthesized poly-(methyl methacrylate) (PMMA) of different molecular weights in different drug-to-carrier ratios in order to investigate their effect on the encapsulation efficiency and drug release kinetics. The prepared formulations were characterized by Fourier transform-infrared (FTIR) spectroscopy, powder X-ray diffractometry, differential scanning calorimetry, yield, drug loading, optical microscopy, surface morphology by scanning electron microscopy (SEM), and in vitro release studies in simulated gastrointestinal tract fluid. The loading efficiency was found in the range from 18?0.34 to 39?0.95 %. The microspheres were spherical, and the mean Sauter diameter (d32) of the obtained microparticles ranged from 26?0.16 to 107?0.58 ?m. The presence of the drug and polymer carriers in the microparticles was confirmed by FTIR spectroscopy and XRD analysis. In vitro dissolution studies showed that the release rate was largely affected by the characteristics of the microparticles, namely the particle size and the nature of the matrix. The release data are best fitted to the Higuchi model with high correlation coefficients (r?).


1970 ◽  
Vol 7 (5) ◽  
pp. 30-36
Author(s):  
Sandeep A Wathore

The formulation of floating microspheres of Betahistine hydrochloride by the o/w emulsification and solvent evaporation method in the presence of tween 80 as an emulsifying agent. The influence of formulation factor Drug: Polymer ratio on particle size, encapsulation efficiency and invitro release characteristics of the microspheres were investigated. The microspheres have been analyzed for their size, drug loading capacity and drug release study. Spherical and smooth surfaced microspheres with desired encapsulation efficiencies were obtained. Slow drug release from microspheres observed up to 12 h. for formulation F4, F5. Optimized formulation F4 was evaluated for FTIR, DSC, SEM. DSC and FTIR studies showed that the nature of pure drug Betahistine hydrochloride remains unaffected till the completion of process of microspheres formation. SEM photographs showed that the Floating microspheres were spherical in nature with smooth surface and uniform distribution of the drug within the microsphere. Keywords: 


Polymers ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1432 ◽  
Author(s):  
Cheaburu-Yilmaz ◽  
Yilmaz ◽  
Kose ◽  
Bibire

The objective of this study was to prepare and characterize physically crosslinked gel formulations of chitosan (CS)-graft-poly(N-isopropyl acrylamide) (PNIPAAm) and polyvinyl alcohol (PVA) for smart delivery of an antifungal drug, Voriconazole, for mucosal applications. For this purpose, cryogels of CS-g-PNIPAAm/PVA and CS/PVA were tested by means of texture profile analysis and rheology to determine optimal matrix properties for topical application. The ratio of 75/25 v/v % CS-g-PNIPAAm/PVA was selected to be used for formulation since it gave low compressibility and hardness (1.2 and 0.6 N) as well as high adhesion properties and non-Newtonian flow behavior. The cryogels and formulations were further characterized by means of FTIR spectroscopy, swelling behavior, texture analysis, scanning electron microscopy (SEM), thermal (differential scanning calorimetry (DSC) and TGA), and rheological behavior. The drug loading capacity and in vitro release profile of the drug, storage stability, and cytotoxicity tests were also performed for the gel formulation. The FTIR, DSC, and TGA results verified the successful formation of cryogels. Swelling studies revealed a pH-dependent swelling ability with a maximum swelling degree of 1200% in acid and 990% in phosphate buffer (pH 7.4). Thermal studies showed that CS-g-PNIPAAm/PVA 75/25 had higher thermal stability proving the structural complexity of the polymer. The loading capacity of Voriconazole was found to be 70% (w/w). The in vitro release profiles of Voriconazole showed Fickian release behavior for CS-g-PNIPAAm/PVA 75/25 gel with an approximate delivery of 38% within 8 h, slower than matrices containing unmodified chitosan. The storage stability test exhibited that the gel formulation was still stable even after aging for two months. Moreover, the cell culture assays revealed a non-toxic character of the polymeric matrix. Overall results showed that the CS-g-PNIPAAm/PVA 75/25 hydrogel has the potential to be used as a smart polymeric vehicle for topical applications.


2021 ◽  
Vol 22 (16) ◽  
pp. 8760
Author(s):  
Zhepeng Liu ◽  
Haini Chen ◽  
Fengmei Lv ◽  
Jun Wang ◽  
Shoujin Zhao ◽  
...  

To optimize the anti-tumor efficacy of combination therapy with paclitaxel (PTX) and imatinib (IMN), we used coaxial electrospray to prepare sequential-release core–shell microparticles composed of a PTX-loaded sodium hyaluronate outer layer and an IMN-loaded PLGA core. The morphology, size distribution, drug loading, differential scanning calorimetry (DSC), Fourier transform infrared spectra (FTIR), in vitro release, PLGA degradation, cellular growth inhibition, in vivo vaginal retention, anti-tumor efficacy, and local irritation in a murine orthotopic cervicovaginal tumor model after vaginal administration were characterized. The results show that such core–shell microparticles were of spherical appearance, with an average size of 14.65 μm and a significant drug-loading ratio (2.36% for PTX, 19.5% for IMN, w/w), which might benefit cytotoxicity against cervical-cancer-related TC-1 cells. The DSC curves indicate changes in the phase state of PTX and IMN after encapsulation in microparticles. The FTIR spectra show that drug and excipients are compatible with each other. The release profiles show sequential characteristics in that PTX was almost completely released in 1 h and IMN was continuously released for 7 days. These core–shell microparticles showed synergistic inhibition in the growth of TC-1 cells. Such microparticles exhibited prolonged intravaginal residence, a >90% tumor inhibitory rate, and minimal mucosal irritation after intravaginal administration. All results suggest that such microparticles potentially provide a non-invasive local chemotherapeutic delivery system for the treatment of cervical cancer by the sequential release of PTX and IMN.


Author(s):  
Sylvester O. Eraga ◽  
Matthew I. Arhewoh ◽  
Ogochukwu A. Meko

Background: The study aimed to evaluate the effect of arachis oil and liquid paraffin on metoclopramide release from transdermal films. Objectives: Batches of metoclopramide films were prepared with hydroxypropyl methyl cellulose (HPMC), arachis oil or liquid paraffin and Tween 80 as plasticizer. The films were evaluated for their physiochemical properties, in vitro and ex vivo drug release and drug release kinetics. Drug-excipient interactions were investigated using Differential Scanning Calorimetry (DSC) and Fourier Transform Infrared (FTIR) spectroscopy. Methods: The transdermal films had a weight range of 0.22-0.24 g, folding endurance of 300-306, percentage moisture content and uptake of 2%-10% and 19%-110%, respectively and drug content of 98%-104%. There was similar condition in vitro release profile for the films but their ex vivo profiles exhibited variable drug release with the P3 (30% arachis oil) giving the highest drug (almost 100%) release.  Results: The release kinetics of metoclopramide followed the first order and Korsemeyer-Peppas models more closely as seen in their correlation coefficients (R2) of 0.9832 and 0.9560, respectively. Drug-excipient compatibility studies showed no interactions between excipients and metoclopramide. Conclusion: The formulated transdermal films showed controlled drug release over a period of 12 h. Arachis oil and liquid paraffin showed similar permeation enhancing ability. These enhanced permeation properties of the films could be helpful in the development of alternative route for metoclopramide administration in the management of emesis with improved patient acceptance.


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